US3772451A

US3772451A - Aerial cable guard

Info

Publication number: US3772451A
Application number: US00326892A
Authority: US
Inventors: J Canavan; W Stewart
Original assignee: Bell Canada Inc
Current assignee: Bell Canada Inc
Priority date: 1973-01-26
Filing date: 1973-01-26
Publication date: 1973-11-13
Anticipated expiration: 1990-11-13

Abstract

A plastic chevron-shaped guard is affixed to the supporting messenger strand of an aerial cable. The chevron protects the cable from damage due to mastication by squirrels and the like and yet permits inspection and access to it.

Description

United States Patent [191 Canavan et al.

111 3,772,451 Nov. 13, 1973 AERIAL CABLE GUARD Inventors: John Andrew Canavan, Agincourt; William Robert Stewart, West Hill, both of Ontario, Canada Bell Canada, Montreal, Quebec, Canada Filed: Jan. 26, 1973 Appl. No.: 326,892

Assignee:

US. Cl 174/41, 174/5 R, 174/136 Int. Cl. ll02g 7/00, H02g 7/10 Field of Search 174/5 R, 40 R, 41,

References Cited UNlTED STATES PATENTS 8/1887 VanDepoele 174/40 R X 4/1890 Penney 191/35 4/1911 VanNostran 174/41 1,183,709 5/1916 Zanella 191/35 1,967,134 7/1934 Short 174/41 2,451,004 10/1948 VanAntwerp 174/41 2,812,380 11/1957 Lehrke 174/41 1 FOREIGN PATENTS OR APPLICATIONS 715,523 9/1931 France 174/5 R 212,514 7/1909 Germany 174/139 221,150 9/1924 Great Britain 174/5 R 181,314 11/1962 Sweden 174/40 R 124,847 3/1928 Switzerland... 174/5 R Primary ExaminerLaramie E. Askin AttorneyJohn E. Mowle [57] ABSTRACT A plastic chevron-shaped guard is affixed to the supporting messenger strand of an aerial cable. The chevron protects the cable from damage due to mastication by squirrels and the like and yet permits inspec tion and access to it.

2 Claims, 2 Drawing Figures AERIAL CABLE GUARD This invention relates to an aerial cable guard and more particularly to one which may be used to protect a multi-pair communications cable from damage caused by squirrels and the like and yet provides ready inspection and access to the cable itself.

BACKGROUND OF THE INVENTION In modern telephone communications, extensive use is made of multi-pair cables having an exterior lead or plastic sheath. This sheath is very susceptible to damage caused by squirrels which bite into the exterior sheath. In some instances, the conductors themselves are damaged while in others, the opening of the exterior sheath allows the entrance of moisture which deteriorates the electrical parameters of the cable.

In the past, cable guards have been used which completely encircled the cable and utilized various locking methods. While preventing damage caused by squirrels, these guards severely restricted access to the communications cable. This resulted in great difficulty in locating leaks and various other faults in the cable. In addition, this combination was not very suitable for splicing drops such as required for telephone or cabletelevision installations. Such a cable guard was usually suited for lashed cable only, i.e., where the supporting messenger strand was helically bound to the communications cable by a lashing wire, as opposed to the type where the cable is hung from the strand by a series of rings. In addition, the encircling guard was often difficult' to installand hard to remove.

SUMMARY OF THE INVENTION The disadvantages of existing cable guards have been overcome by providing a plastic chevron-shaped guard which is placed over the cable combination and affixed thereto.

Thus, in accordancewith the present invention there is provided a combination of a multi-conductor electrical communications cable and a supporting messenger strand which runs along the length of the communications'cable. In addition, an upwardly directed plastic chevron is longitudinally disposed over the cable with its interior apex in contact with at least portions of the supporting cable. Means are also provided for affixing the chevron to the supporting cable so that the communications cable is exposed on the underside of the chevr'on yet protected from damage by squirrels and the like. Should the squirrels bite into the chevron guard, they can do so without causing any damage to the communications cable itself. Thus, this arrangement still enables them to live in the immediate area. Such a structure is feasible because of the realization that the diameter of the cable is at least several times that of the messenger strand. Since the chevron guard is affixed only to the strand rather than the overall aerial cable assembly, it is restrained from rotating around the assembly in strong winds. This negates the possibility of the chevron collecting rain, snow or ice and consequently placing a severe structural stress on the cable assembly.

BRIEF DESCRIPTION OF THE DRAWINGS An example embodiment of the invention will now be described with reference to the accompanying drawings in which:

FIG. 1 is a side elevational view of a section of an aerial cable system employing a cable guard in accordance with the present invention; and

FIG. 2 is a cross-sectional view of the aerial cable taken'along the line IIII of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT tic chevron 12. A conventional plastic clip 15 is inserted through the

holes

13 and 14 between the cable 10 and the strand 11 and thence back around the exterior apex 16 of the chevron 12. The ends of the clip 15 are coupled together in any one of a number of well known ways.

As shown in the drawings, the bottom of the chevron 12 is open thereby permitting inspection and access to the 'multi-paired cable 10 without removal of the chevron 12. Because the diameter of the cable 10 is several times that of the strand 11, the chevron 12 is effectively prevented from rotating around and under the cable 10 and thence acting as an eavestrough which could result in severe structural stress on the cable assembly caused by rain,-snow and ice loading. Because the chevron 12 is made of plastic, it will readily spread thereby permitting the use of cable with a diameter approaching that of the length of the legs of the chevron 12.

The plastic guard 12 may also be used on aerial cable where the cable 10 is suspended by a plurality of rings from the strand 11 at periodic intervals. In installations of this nature, the cable 10 may protrude below the bottom of the chevron 12 but still retains the guard featuresWith both installations, squirrels and other such animals may scamper along the top of the chevron 12.

If they do chew into the chevron 12, they will eventually strike the messenger strand 11 with no resultant damage to the communications cable 10.

In a typical installation, the guard 12 is made of rigid polyvinylchloride having a wall thickness of 0.06 inches. The guard 12 is supplied in lengths of up to 10 feet and can be readily cut in the field for installation.

What is claimed is:

1. In an aerial cable system, the combination com prising:

a multi-conductor electrical communications cable having an exterior sheath; and

a supporting messenger strand for at least periodically supporting said communications cable along its length between spans; the improvement comprising: an upwardly directed plastic chevron, longitudinally disposed over said cable and said strand, having its interior apex in contact with at least portions of said messenger strand; and

means affixing said chevron to said messenger strand;

whereby stantially adjacent said apex; and

,in which each of the means affixing the chevron comprises an annular clamp which passes through said pair of holes, under said supporting cable and over the exterior apex of the chevron.

Claims

1. In an aerial cable system, the combination comprising: a multi-conductor electrical communications cable having an exterior sheath; and a supporting messenger strand for at least periodically supporting said communications cable along its length between spans; the improvement comprising: an upwardly directed plastic chevron, longitudinally disposed over said cable and said strand, having its interior apex in contact with at least portions of said messenger strand; and means affixing said chevron to said messenger strand; whereby said communications cable is exposed on the underside of the chevron yet protected from damage by squirrels and the like which run therealong.

2. The combination as defined in claim 1 in which said chevron has pairs of periodically spaced holes along its length, one on each leg of the chevron substantially adjacent said apex; and in which each of the means affixing the chevron comprises an annular clamp which passes through said pair of holes, under said supporting cable and over the exterior apex of the chevron.